Basic soundproofing. I need some input

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For awhile I've been considering adding some soundproofing to my Focus. I've read a lot online about people using roofing membrane material as sound deadening, as it is similar to a lot of 'professional' sound deadening products. What I really want to know is: how much do I really need to apply?

I've heard that even a 1' x 1' square applied to a panel can make a HUGE difference in absorbing vibration and some sound. Is this true? If so, I can easily apply a little sound deadening to each panel on the car (doors, trunk, etc).
 
Without knowing the precise location the sound is originating from, you're better off applying as much as possible. Doors, floors, ceiling, etc. I have seen some people go nuts and gut the entire interior.

It comes down to "mass". The thicker and heavier stuff deadens the sound better. So yes, a single 12"x12" square can provide some relief, depending on the type of noise you have making its way into the cabin.
 
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Yes, just doing the middle of the panel as best you can is usually enough. Doing up to the edges does not help as much because what the sound deadening does is prevent ringing of the metal. The edges are not going to ring because they are pretty stiff. Its the middle of the panel that is going to do it.
 
Are you atteuating a loud sound system?
Are you quieting the car from out side noise?
These require different approaches and materials.
Cheap jute carpet underlayment with duct tape and construction glue works well for ambient noise reduction.
 
Originally Posted By: mechtech2
Are you atteuating a loud sound system?
Are you quieting the car from out side noise?
These require different approaches and materials.
Cheap jute carpet underlayment with duct tape and construction glue works well for ambient noise reduction.


Yes, I am trying to quiet some of the ambient/road noise.
 
Originally Posted By: mechtech2

Cheap jute carpet underlayment with duct tape and construction glue works well for ambient noise reduction.


I did this on my 09 Ranger on the door panels. Made a big (enough for me) difference without costing stupid money. I didn't break any of the plastic seals on the door so shouldn't be a moisture problem.
 
Yes, it can make a HUGE difference.

Some of it is heavy, but there are a lot of choices now. I have used this in several cars and trucks and the difference is well worth the effort.
 
I used "FatMat",bought a bulk pack 50 sq ft & put it down.Self adhesive and you must roll it down tight.I did everything but the headliner. A huge improvement-worth the cost and effort.
 
I did my headliner, doors, floor [under the carpet] and trunk area with carpet underlayment and also some extra in spots of the high density under hardwood foor insulation.
A couple of hours and the car was MUCH nicer.
My ZX2 needed it more than a Crown Vic, though.
 
Originally Posted By: jhMalibu
Originally Posted By: mechtech2

Cheap jute carpet underlayment with duct tape and construction glue works well for ambient noise reduction.


I did this on my 09 Ranger on the door panels. Made a big (enough for me) difference without costing stupid money. I didn't break any of the plastic seals on the door so shouldn't be a moisture problem.


Just curious... Did you put the jute on the plastic door skin, or on the metal inside of the door? I could easily pull all of the door skins off and put a layer of jute on them, without even touching the plastic/moisture seals. Doing it this way wouldn't really dampen door vibrations, but it WOULD block sound I'd think.
 
Outside of the plastic is the same as inside, for noise attenuation.
If the door panel fits back on, it will work great. Why disturb the plastic if you don't have to?

You can also spray bedliner - any heavy coating - on the inside of the doors [under the plastic on the inside door skin]. Make sure the drains are free afterwards!
Don't plug the drains!
Don't use stinky stuff - it'll take forever to go away!
 
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I have decided on what I'm going to do. After some careful listening while driving, it seems that a good majority of the road noise comes from the trunk area. So I'm going to deaden that first, using 'Quick Roof' from Home Depot (same as Peel & Seal from Lowe's). I'm going to do literally every surface in the trunk: floor, spare tire well, sides, trunk lid, and rear deck. I'm picking up the supplies tomorrow morning and will probably have it applied before the end of the work week, but it'll depend on my schedule. If all goes well and I notice some positive results, I'll move on to doing the doors also.

Part of me feels that it's not worth it... it's just a Ford Focus. But the other part of me feels that for a few bucks, why not give it a shot? After all, I plan on driving this car until it dies, so why not make it 'user-friendly'? The '08-'11 Foci (basically the same car, just facelifted) is much quieter, thanks to better sound deadening. Hopefully I can find a way to put my '07 somewhat on par with its newer siblings.
 
I have tried and use undercarpet padding, dynamat knockoff and neoprene sheets. I recommend dynamat for large flat metallic areas, but the most muffling and quietest effect I got from neoprene sheets to replace the vapor wrap found in doors and undercarpet padding above the wheel wells in the trunk.

Neoprene sheets in various thickness can be bought cheap off ebay and carpet padding super cheap at your local Home Depot or Lowes.
 
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My 1996 Contour has lots of "road noise" emanating from the trunk. I know it's from the trunk because when we go on vacation and the wife packs enough luggage for 2 months for a 10 day vacation it's real quiet, she's not though
grin2.gif
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Whimsey
 
Update: So far I have covered the spare tire well, floor, driver's side wheel well, driver's side wall, and 'latch' side of the trunk. I still have to cover the passenger's side, rear deck, and trunk lid, and put the carpeting back. Still, it seems quieter than before, even though I'm not done yet AND the carpeting is not back in fully. The best part is... No smell! My car baked in 89 degree heat all day at work, and I had to try really really hard to notice any smell at all, even when I opened the trunk itself. So far, so good.
 
I got some Hardie housewrap from Lowes. It a tape for installing windows and doors in siding. It's Butyl Rubber with no asphalt. It's a 6'' w by 75'Long. I'm starting to install it in my old corolla. With the heat here in Dallas, I did not want any asphalt smell.
 
Hey, I've been thinking about soundproofing lately, and was pleased to find this old thread. I would like to cut the road-noise level in both of our vans, an '09 Mazda 5 and an '09 Kia Sedona.

My previous attempt at this was fairly successful, although I won't go the same route. When I was a teenager I owned a '70 Toyota Corolla for awhile. It was pretty basic - 1200 cc, 4-speed manual, no AC, no PS, no radio, and no carpeting. The floor was covered with a rubber liner, and the car was crazy loud. After about a year I ripped out the rubber matting, and glued down (with contact cement) blue shag carpet. I thought it looked pretty neat (it was the 70s after all) and it cut the road noise dramatically.

Well, fast forward to the present day. I will keep the factory carpeting in both vehicles, and want to install some sort of sound-damping material under the carpet. I've been surfing all over the 'net, and it seems that there are many opinions. I respect the knowledgeable folks here, and figure that in the five years since this discussion lapsed there have been others who've given this a try.

Please jump in - share your experiences successful or otherwise.

Thanks in advance!
 
I went to Home Depot and got a rubber door mat for cheap, cut it to fit under the carpet (front, rear & trunk/hatchback) of a couple of beater cars and trucks I owned in the past. I used duct tape to seal up the seams of the cut pieces. Easy install. My opinion, it worked as good as the expensive dynamat stuff when it comes to sound proofing. It didn't make the car Cadillac quiet, but it did help some
 
Whatever you do, get the PROPER stuff. There are lots of cheap-o options out there, and I HAVE heard a number of success stories with them, but I've also heard a ton of major horror stories with them, especially in areas where there's lots of heat.

Before you do anything, watch some videos made by people who REALLY know what they're doing, to get some solid fundamental info. IMHO, one of the best channels on YouTube that you can watch for car audio info is CarAudioFabrication. Mark really knows his stuff, and presents it incredibly well. He's actually got an entire video series on sound deadening.

You can find this video series HERE.

As far as materials - There's a whole range of products, some of them extremely expensive, and some not too bad. Whatever you do, get the right stuff. Once the weather here in Phoenix cools back down (it's supposed to hit 117 today), I plan to do my car using This Noico branded product which has excellent reviews, and This Noico sound deadening foam mat under the carpet to further isolate sound.
 
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